Even knives of hight quality do not always ensure their real sharpness if not sharpened properly to their each use.
In order to exercise their best performance,sharpening the edge to be strong and fine is essential.

tips

Even knives of hight quality do not always ensure their real sharpness if not sharpened properly to their each use.
In order to exercise their best performance,sharpening the edge to be strong and fine is essential.

Preparations

1.Place stones in water deep enough to cover them entirely,Leave them until absorb the water well enough.

2.If the sharpening stone surface is not flat,use the rough grain stone and rub the surface with some water until flat.

Double-edged knives

Whetstones you should be using are #180 ～ 220 for Rough Sharpening, #600 ～ 1500 for Mid Sharpening, and #2200 ～ 5000 for Finishing.First, using the whetstone for Rough Sharpening, sharpen the edge on
both sides even by same angle. You adjust the total shape of the blade in this step. When the blade has some gristle, use the whetstone for Mid-Sharpening and repeat the process. When roughness on the edge
lessons, stand the blade a little, and use less force holding the blade. Keep sharpening until smooth.If you need finer (more detailed) edge, use the whetstone for finishing.

When sharpening, if the angle of the edge on the whetstone is too obtuse, roughness can not be removed, and the edge becomes too thin so the blade can be easily chipped. The edge does not have the desired sharpness either. If the angle is too acute, the blade dose not slice well. The edge will not cut in smoothly even though the edge may be durable.Approximate angles and the proportion of the sharpening on the front to the back are described below.

Edge Angles
Thin knives such as Chef's Knife, Paring knife should be sharpened by 8°～ 10°against the whetstone. Thick knives such as Boning Knife should be sharpened by 12°～ 15° Knives such as Chicken knife and Boning Knife should be sharpened 20°～ 30°for the front side and 2°～ 3°for the back side.

Proportion
Three - Seventh Sharpening ----- Sharpen both sides at same angle at ration of 30% on the back and 70% on the front.
Double side sharpening ----- Sharpen both side ratio.
One - Side Sharpening ----- Sharpen mainly the front side but sharpen the back side slightly angled also.

Edge angle will vary by the knife types. Their purpose and the method of how the knife is used will determine the edge. If the edge is sharpened too flat, it becomes fragile and will not cut in smoothly. A curve edge is desirable.

Chef's Knife,Paring knife

Chicken knife and Boning knife

Single-edged Knives

Whetstones you should be using are #180 ～ 220 for Rough Sharpening, #600 ～ 1500 for Mid Sharpening, and #2200 ～ 5000 for Finishing.
First, sharpen the section between SHINOGI and HASAKI (edge) on the front of the blade even: Rough Sharpening. You adjust the total shape of the blade in this step. When the blade has some gristle, next step is Mid-Sharpening. Use a finer whetstone and repeat the process. Sharpen the back of blade as well. For the back side, use a flat whetstone and sharpen from about 1 mm from the tip. When roughness on the edge lessons, stand the blade a little and use less force holding the blade. Keep sharpening until smooth. If you need finer (more detailed) edge, use the whetstone for finishing.Single-side blade Japanese knives are slightly bowed on the back for easy sharpening. Make sure to sharpen remaining this shape. Sharpening too much on back will remove the shape. The range that should be sharpened on the back needs to increase up to 2 mm for knife using to slice tougher products.

Edge Angles
When sharpening, if the angle of the edge on the whetstone is too obtuse, roughness can not be removed, and the edge becomes too thin so the blade can be easily chipped. The edge does not have the desired sharpness either. If the angle is too acute, the blade does not slice well. The edge will not cut in smoothly even though the edge may be durable.Edge angle will vary by the knife types. Their purpose and the method of how the knife is used will etermine the edge. A slight angled edge or a curved edge is desirable.